US4534359A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and means for determining frequency selective tissue attenuation in a baseband ultrasonic imaging system
Assignee: General Electric Co
•
Filing: 1982-12-02
•
Granted: 1985-08-13
•
Expires: 2002-12-02
Abstract
Abstract Ultrasonic wave attenuation in passing through tissue is determined from frequency changes in reflected ultrasonic waves passing through the tissue. In a baseband ultrasonic imaging system in which transducer generated signals are coherently detected by mixing the signals with a fixed frequency signal both in phase and in phase quadrature, a measure of frequency change in the reflected ultrasonic signal is obtained by measuring phase shift in a side band of the mixed signals.
Inventors
- 👤 Stockton M. Miller-Jones
- 👤 Stephen W. Flax
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:42
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/52; G01S7/52017; G01S7/52023; G01S7/52036
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
99 words
In a baseband medical ultrasonic imaging system in which transducer means receives reflected ultrasonic waves and generates input electrical signals and demodulator means mixes said input electrical signals with a demodulator signal to obtain a high resolution focused image signal, a method of determining frequency shift of said input electrical signals over a period of time comprising the steps of filtering the output signals of said demodulator means to obtain a sideband signal of said mixed input signals and demodulator signal, detecting phase change of said sideband signal, and differentiating said detected phase change over said period of time.
Claim 2
Dependent Claim
99 words
In a baseband medical ultrasonic imaging system in which transducer means receives reflected ultrasonic waves and generates input electrical signals and demodulator means mixes said input electrical signals with a demodulator signal to obtain a high resolution focused image signal, a method of determining frequency shift of said input electrical signals over a period of time comprising the steps of filtering the output signals of said demodulator means to obtain a sideband signal of said mixed input signals and demodulator signal, detecting phase change of said sideband signal, and differentiating said detected phase change over said period of time.
Claim 3
Dependent Claim
84 words
In a medical ultrasonic imaging system, a method of determining frequency change in a reflected ultrasonic signal as a measure of tissue attenuation and gain control comprising the steps of generating an electrical signal in response to said reflected ultrasonic signal, mixing said electrical signal with a fixed frequency signal to obtain a beat signal, detecting phase change in said beat signal, and differentiating said phase change over a period of time as a measure of said frequency change over said period of time.
Claim 4
Dependent Claim
84 words
In a medical ultrasonic imaging system, a method of determining frequency change in a reflected ultrasonic signal as a measure of tissue attenuation and gain control comprising the steps of generating an electrical signal in response to said reflected ultrasonic signal, mixing said electrical signal with a fixed frequency signal to obtain a beat signal, detecting phase change in said beat signal, and differentiating said phase change over a period of time as a measure of said frequency change over said period of time.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-08-12 | 1989-02-11 | 1989-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-12 | 1993-02-11 | 1993-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-12 | 1997-02-11 | 1997-08-13 | $7700.00 | Window Closed / Lapsed |